In Japanese Patent Application Publication No. 2010-103326 (JP-2010-103326 A) (hereinafter referred to as Patent Document 1), there is disclosed an IGBT that has a top body region, a floating region, and a bottom body region. In manufacturing this IGBT, after a trench gate electrode is formed, p-type impurities are implanted in such a manner as to stop within a depth range of the top body region, n-type impurities are implanted in such a manner as to stop within a depth range of the floating region, and p-type impurities are implanted in such a manner as to stop within a depth range of the bottom body region. Thus, the top body region, the floating region, and the bottom body region are formed.